Polyethers containing hydantoin rings as antistatic agents for synthetic fibers and foils

ABSTRACT

This invention relates to synthetic fibres, threads and foils of polymer with permanent antistatic properties which contain 0.5 to 15 percent by weight of polyethers containing hydantoin rings. Polyethers containing hydantoin rings according to the invention are well compatible with the polymers and well resistant against washing.

United States Patent Wolf et al. Dec. 23, 1975 POLYETHERS CONTAININGHYDANTOIN [58] Field of Search 260/78 S, 88.7 R, 88.7 B, RINGS ASANTISTATIC AGENTS FOR 260/DlG. l7, DIG. l9

SYNTHETIC FIBERS AND FOILS [75] Inventors: Gerhard Dieter Wolf,Dormagen; References Cited Helmut Engelhard, Leverkusen; UNITED TEPATENTS Franc Bentz an of 3,728,305 4/1973 Wells 260/78 s Germany3,755,497 8/1973 Weedon et al 260/860 [73] Assignee: BayerAktiengesellschaft,

Leverkusen-Bayerwerk, Germany Primary Examiner-Harold D. Anderson l4,Attorney, Agent, or Firm-Plumley & Tyne! [21] App]. No.: 397,419

[57] ABSTRACT [30] Forelgn Apphcatlon Pmmty Data This invention relatesto synthetic fibres, threads and Sept. 15, 1975 Germany 2245335 foils fp ly with permanent antistatic properties which contain 0.5 to 15percent by weight of poly- [52] 260/88'7 B; 260/78 S; 260/85'5 ES;ethers containing hydantoin rings. Polyethers contain- 260/85.5 S;260/79.3 M; 260/85.5 B;

260/85.5 XA; 260/92.8 A; 260/93.5 A; 260/94.9 GD; 260/DIG. 17; 260/DIG.l9; 260/309.5

Int. Cl. C08F 122/30 ing hydantoin rings according to the invention arewell compatible with the polymers and well resistant against washing.

8 Claims, No Drawings POLYETI-IERS CONTAINING HYDANTOIN RINGS ASANTISTATIC AGENTS FOR SYNTHETIC FIBERS AND FOILS This invention relatesto synthetic threads, fibres, foils and films with pennanent antistaticproperties.

Shaped products produced from polymers, e.g. fibres produced frompolyacrylonitrile, polypropylene, polyamides or polyesters, generallyhave the undesirable property of becoming electrically charged, whichconsiderably restricts their range of commercial applications. Thisunwanted electrostatic charging occurs when the surface resistance ofthe fibres is more than Ohm.

Various measures'have already been employed to overcome thisdisadvantage. It has frequently been attempted to increase theelectrical conductivity by a surface treatment with antistaticpreparations of the fibres or of the textile products produced fromthem. It is often found, however, .that the antistatic effect therebyobtained is not sufi'rciently permanent.

According to another method, an antistatic finish is obtained byapplying aqueous solutions of suitable agents to fibres which are in anaquagel state (see German Pat. Specifications Nos. 1,469,913 and1,965,631 The difficulty in this method lies in observing specificoperating conditions.

It is also known to mix polyacrylonitrile, for example, with a'secondacrylonitrile copolymer which contains from 30 to 80 percent by weightof a polyethylene oxide methacrylate and then to spin this mixture (seeGerman Pat. Specification No. 1,645,532). Excessively high proportionsof polyethylene oxide, however, cause yellowing of the fibres whenexposed to heat or light so that stabilizers must then be. used toovercome this disadvantage (see .G'erman Ofienlegungschrift No.2,138,839). 1

Those processes which consist in increasing the electrical conductivityby copolymerising suitable comonomers generally have the disadvantage ofsubstantially altering the characteristic and advantageous properties ofpolymers which are modified in this way.

Another method frequently employed for reducing the static charge onpolymers consists in adding polyethers on other suitable compounds, inmost cases compounds which contain polyethers, to the solutions orsolvent-free melts of these polymers before they are shaped. lt is verydifficult, however, to find compounds of this type which are bothwash-resistant, i.e. remain in fibres of such polymers even afterrepeated washing with alkaline detergents, and sufficiently compatiblewith the polymers mentioned above. Polyethers and many compounds whichcontain polyether segments have the additional disadvantage of reducingthe lightfastness of the polymers to which they are added.

The polyethers according to this invention which contain hydantoin ringscombine several advantages within themselves. The hydantoin rings renderthem highly compatible with the polymers and impair the antistaticproperty which is very resistant to washing. Thus, for examplebis-urethanes prepared from a polyetherdiol (average molecular weight.1000) and stearylisocyanate 'have poor compatibility withpolyacrylonitrile solutions whereas compounds with a similarstructurebut, in addition, containing a hydantoin ring in accordance with thisinvention, have surprisingly good compatibility. Another great advantageof 2 these compounds is that the hydantoins have the effect of ensuringsubstantially improved lightfastness of the polymers. I

This invention therefore relates to synthetic threads, fibres, foils andfilms with permanent antistatic properties made of polymers obtained bypolymerisation, polyaddition or polycondensation, which contain 0.5-15percent by weight, preferably l-l0 percent by weight, of polyetherswhichcontain one or more hydantoin'rings as represented by the followinggeneral group, Y represents a bivalent C to C hydrocarbon group whichmay be substituted by halogen, alkyl, N0 or CN, and Hyd represents abivalent group of the formula 1 R' o R l R represents a C to C alkyl,cycloalkyl, aryl, aralkyl or alkaryl group which may be substituted byhalogen, alkyl, N0 or CN,

R may have the same meaning as defined for R or represent the group-(C,,,H ,,,O) -(C,,H ,,O),,-X,

R" and R represent a C to C alkyl or aryl group or together represent aC to C cycloalkyl group,

n and m represent an integer of from 2 to 6 and p and q represent 0 oran integer of from 1 to 50, preferably 5 to 30, and at least one of thetwo symbols p or q must represent an integer- 0.

The group of polymers should be understood to include in particularpolyacrylonitrile or Copolymers of acrylonitrile with (meth)-acrylicacid esters, (meth)- acrylamides, N-vinyl lactams, vinyl-,(meth)-allyl'esters or ethers, vinyl or vinylidene halides,alkylvinylpyridines, vinylimidazoles, (mono)-dialkylaminoalkylacrylatesor methacrylates or their quaternised derivatives, vinyl-,(meth)-allylsulphonic acids, vinyl-, (meth)-allylphosphonic acids ortheir esters, as well as polyalkylenes, polystyrenes, polyacrylates ormethacrylates, polyvinyl or polyvinylidene halides and mixtures of thesepolymers.

The invention also relates to permanently antistatic threads, fibres,foils and films of polyamides, of the kind described in Die Polyamide",by H. Hopff, A. Miiller, and F. Wenger, Springer Verlag Berlin,GiSttingen, Heidelberg, 1954, pages 31,32 and 153 and inKunststoff-Handbuch Volume IV, Polyamide, Carl l-lans'er Verlag Munchen,1966, pages 143 and 144. Polyimides may also be suitable polymers forthe purpose of this invention, for example those mentioned in GermanAuslegeschrift No, 1,082,314; French Patent Specification No. 1,283,378;US. Pat. Specifications I p 3 .7. g Nos. 3,179,634 and 3,300,420 andBritish Pat. Specifications Nos. 1,009,956; 1,160,097; 1,168,978 and1,056,564. Polyesters and polyurethanes, e.g. those mentioned, in;Fibres from Synthetic Polymers, Rowland Hill, Elsevier PublishingCompany, New York, N.Y 1953, pages 144446, may also be used forproducingtheendproducts according to the invention.

The polyethers containing hydantoin rings in. accordance with thegeneral formula I are prepared by methods knownper se, for example byreacting ar-aminocarboxylic acid nitriles with alkylisocyanates in inertsolvents. The urea derivatives obtained from this reaction may becyclised in solution or in suspension, preferably with the aid of acidcatalyst, e.g. in a mixture of ethanol and concentrated hydrochloricacid, to produce the 3-alkylhydantoins: Polyethoxylation is preferablycarried out in the melt after the addition of a basic catalyst such asan alkali metal hydroxide or alkali metal alcoholate, although, inprinciple, ethoxylation could also be carried out in solution in aninert solvent. Ethoxylation with glycol carbonate, which has alreadybeen described :in the literature, has also been found to besatisfactory.

Instead of reacting the hydantoins with one alkylene oxide, they may bereacted with a mixture of two or more alkylene oxides. In that case, itis preferred to add the various alkylene oxides successively orperiodically so that uniform blocks can be formed.

Since a given alkylene oxide is not incorporated uniformly butstatistically distributed, the index p or q in the formulae representsthe average degree of polyaddition of alkylene glycol chains of variouslengths.

Alkoxylation carried out with ethylene oxide alone is most effective forthe purpose of the invention and therefore preferred although, in thecase of some compounds, it has been found advantageous to carry out atreatment with propylene oxide prior to ethoxylation.

These polyethers which contain a hydantoin ring may be reacted with amonoisocyanate, an alkyl, cycloalkyl or aryl isocyanate', preferablystearyl isocyanate, in the melt or in solution, to form a urethanegroup. This procedure is suitable for increasing the wash resistance ofthe, compound if it is to be used as additive for polymers. lngeneral itis found that, for a given degree of ethoxylation, those hydantoins inwhich the terminal hydroxyl functions are converted to. urethane groupshave'very permanent antistatic properties because of their much higherresistance to washing.

1f, instead of reacting the polyether containing a hydantoin-ring with amonoisocyanate, it is reacted with a diisocyanate in a molar ratio of 2mols of monofunctional hydantoin polyether to 1 mol of diisocyanate,then compounds of the general formula II are obtained. The diisocyanatesused may be known aliphatic or aromatic diisocyanates, e.g. 4,4-diisocyanatodiphenylmethane or hexamethylene diisocyanate.

To prepare polyethers of the general formula Ill which contain twohydantoin rings, for example, aaminocarboxylic acid nitriles are reactedwith a diisocyanate such as 4,4risocyanatodiphenylmethane orhexamethylene diisocyanate in a molar ratio of 2:1, preferablyin aninert solvent. The resulting diurea may advantageously be cyclised tothe dihydantoin in an acid medium. Variousv processes are known in theliterature but the method of heating in a mixture of ethanol andconcentrated hydrochloric acid, for example in proportions of.4:.1, hasbeen found to be particularly atedat both free Nl-l; groups as describedabove. If desired, the free hydroxyl groups maybemasked with isocyanatesto increase the-hydrophobic character of the molecules as a whole.

Polyethers and polyether urethanes with hydantoin rings prepared asdescribed above are addedto the spinning solutions or melts of thepolymers in concentrations of 0.5 to 15 percent .by weight, preferably 1to 10 percent by weight, based on the polymers, before the polymers areshaped.

Formation of these threads, fibres, foils or films which have beenmodified by the additives is carried out by the usual well knownprocesses. 1

The resistance of the fibres according to the-invention, for whichfigures are given inithe examples, was determined by means of acommercial high resistance ohmmeter (manufactured by Knick) by measuringbetween the plates of two electrodes spaced apart by 1 cm and using ameasuring voltage of V, in accordance with DIN 54345. Before eachmeasurement, the

fibre material was conditioned for 72 hours in a stan-.

dard. atmosphere of 50 percent relative humidity at 23 C.

Fibres. produced according to the invention have an.

electric surface resistance of between 10 and 10 Ohm .at 50 percent r.Hand 23C. Garments such'as suits, skirts, Waistcoats or jacketsmanufactured from these fibres show hardly any. signs of electrostaticcharging or any of the known phenomena due to electrostatic chargingsuch as sticking of the garments to their hangers soiling due toattraction of dust, crackling noises due to discharge. or electricshocks. The fibres according to the invention canbe dyed with the usualdyes withoutanyloss of their excellent antielectrostatic character. Thefibres are particularly advantageous for use in fabrics which wouldotherwise require a subsequent antistatic finishing treatment, forexample curtain fabrics. Fibres used in this way are not found to 15parts by weight of an approximately 10 percent methanol ic solution ofsodium methylate were added to 142 parts by weight of-3,5,5-trimethylhydantoin in a three-necked flask with a stirrer and adistillation condenser attached to it. The mixture was slowly heatedwith stirring to evaporate the alcohol. The temperature was then raisedtol70C and, after displacement of the remaining air with nitrogen,ethylene oxide was introduced until a weight increase of 330 parts byweight was obtained. The thick yellow oil obtained was 7 satisfactory.Thisbis-hydantoin may be polyalkoxylpressure filtered to remove a slightcloudiness. The molecular weight was found by determining the hydroxylnumber. OH 3.7, molecular weight 460.

100 parts by weight of this polyether were heated to 100C undernitrogen, 70 parts by weight of stearyl isocyanate were added dropwiseover a period 0f-2 hours and the reaction mixture was then stirred for 2to 3 hours at 100C. The reaction product was taken up with 250 parts byvolume of dimethylformamide and again filtered to remove a slightinsoluble residue. The solids content of the solution was 41 percent byweight.

This solution of 3,5,5-trimethyll-polyethylene oxideurethane was used toprepare a solution in dimethylformamide of a mixture of 90 percent byweight of a polyacrylonitrile (K-value 81) and percent by weight of thepolyethoxylated urethane. The solution was spun dry at a viscosity ofabout 260 poises (85C). The fibres had a tensile strength of 3.9 g/dtexand an elongation of percent.

The antielectrostatic action of the additive was determined by measuringthe surface resistance of thefibres at 23C and 50 percent relativehumidity as already mentioned above. Resistance of sample obtained(unbleached: 5 10"0; resistance of sample after 10 washings: 3 10"(1.

Since the polyacrylonitrile used in the mixture contained an acidadditive, the fibres obtained from the EXAMPLE 2 Antistatic action of Amixture of 90 percent by weight of polyacrylonitrile and 10% by weightof the polyethoxylated 3,5,5 trimethylhydantoin described in Example 1was spun dry. The fibres were found to have the following surfaceresistances: Fresh fibre: 9 10 0; Fibreafter 5 washings: 3 10"0. Afterthe sixth washing, the surface resistance had already increased to 2 l0and was therefore too high for any antielectrostatic effect.

EXAMPLE3 0 CH I CH CH ,N (Cl-l cH -0) H as additive This3,5,5-trimethyl-hydantoin polyethylene oxide was prepared by theethoxylation method described in Example I. Fibresspun from a mixture ofpercent by weight of polyacrylonitrile and lOpercent by weight of thecompound were found to have the properties shown below. Tensilestrength: 2.5 g/dtex Elongation: 14 percent Electric surface resistance:

in fresh, unbleached fibre: 9 10 9 after 8 washings: 3 l0Q.

EXAMPLE 4 188 parts by weight of 3-stearyl-5,S-dimethyIhydantoin and 3.5parts by weight of solid potassium hydrox- EXAMPLE 5 Preparation andantistatic action of 3,5,5-Trimethylhydantoin was ethoxylated 15-fold asdescribed in Example l to produce a product with a hydroxyl constant of2.1 percent, corresponding to a molecular weight of ==8l0.

405 parts by weight of the polyether were taken up with 300 parts byvolume of dimethylformamide, and a solution of 65 parts by weight ofdiphenylmethane-4,4'- diisocyanate in 200 parts by volume ofdimethylformamide was added dropwise at room temperature. The reactionmixture was stirred for 5 hours and then heated to 60C for 2 hours.

This solution was again used for preparing spinning solutions, in thiscase containing a) 90 percent by weight of polyacrylonitrile (PAN) and10 percentby weight of diurethane (DU) and M95 percent by weight of PANand 5 percent by weight of DU, and the solutions were spun to formfibres.

Measurement of the surface resistance yielded the following results (50percent r.H, 23C):

fresh fibre after H) washings u) 5 10 4 lo -Q b)8- 10"!1 9' l".Q

EXAMPLE 6 Preparation and antistatic action of a. n 8, b. n 19 150 partsby weight of stearyl isocyanate were added to 200 parts by weight ofthis compound under an atmosphere of nitrogen at 100 to 120C for onehour and the reaction mixture was then stirred for a further 4 to 5hours. The product was taken up with 380 g of dimethylformamide at roomtemperature and stirred until it was almost completely dissolved. It wasthen filtered to remove a slight residue (5 parts by weight) and used toprepare a solution in dimethylformamide which, based on the solidscontent, consisted of 90 percent by weight of polyacrylonitrile (K-value84) and percent by weight of the adduct described above and which had aviscosity of 280 poises (85C).

The surface resistance of threads which had been produced from thissolution and stretched by 123.8 was found to be 4 10" in the freshthreads and 6 10 in threads which had been washed 10 times with analkaline detergent.

b. 5,5-Dimethylhydantoin was ethoxylated by the method described undera) until the molecular weight had increased to 1860. 465- Parts byweight of this polyethylene oxide were reacted with 150 parts by 8weight of stearylisocyanate at 100 to l20C as described above to producea diurethane which contained polyethylene oxide units and after this hadbeen left to react for a further 5 hours at ll0C it was used to preparesolutions in dimethylformamide which had the following composition basedon the solids content:

A l. percent by weight of polyacrylonitrile (K-value 84) and 10 percentby weight of diurethane;

2. percent by weight of polyacrylonitrile and 5 percent by weight ofadduct. The solutions were then spun dry.

The surface resistance of the fibres (Q, 50 percent r.H., 23C) was foundto be as follows:

after l0 washings CH 5 CH N- CH -C -0 H c 2 n 70 parts by weight of4,4'-bis-[5,5""rdimethylhydantoinyl-(3")]-diphenylmethane and 1 part byweight of solid potassium hydroxide were mixed with 250 parts by weightof glycol carbonate and carefully heated to 150C while nitrogen waspassed through. The reaction mixture was then stirred for 15 hours atthis temperature, carbon dioxide being liberated. 85 Parts by weight ofvolatile constituents were then evaporated off under a high vacuum (0.9mm) at to C.

The tough, pale brown residue was soluble in dimethyl formamide andinsoluble in water and, when mixed to an extent of 10 percent by weightof polyacrylonitrile in dimethylformamide, it yielded a homogeneous,clear, colourless solution which was spun to form threads.

The surface resistance of the fibres was found to be 8 10 0 in freshfibres and 9 10 after 10 washings.

EXAMPLE 8 Antistatic action of nylon-6-granulate. The homogeneousmeltedmixture I was spun from an extruder and the resulting threads werestretched. Their surface resistance was found to be 8 10 in the freshthreads and 10 after 10 washings.

EXAMPLE 9 Antistatic action of used in polyamides.

ll (CH2CH2-0) -c-m-(cu 74H} Compound 1 percent by weight of abis-urethane of diethoxylated 5,5-dimethylhydantoin prepared asdescribed in Example 6 was incorporated with a polyamide-6 melt in anextruder and extruded to form cables which were then granulated.

The homogenised granulate was then processed in a chip rolling mill toproduce fibres with a titre of 4 dtex.

The following results were obtained from measuring the electric surfaceresistance:

fresh fibres: 7

after 10 washings: 8 10'".

We claim:

1. A fiber, thread or foil of a synthetic polyacrylonitrile polymer withpermanent antistatic properties, which contains 05-15 percent, by weightof the total, of polyethers containing hydantoin rings as represented bythe formula X n 2n)p m 2m)q R, in which X represents hydrogen or thegroup R represents a C -alkyl, cycloalkyl, aryl, aralkyl or alkarylgroup or halogen alkyl, N0 or CN derivatives thereof;

R has the meaning given for R or represents the g p rn zm )q'( n 2n )p'R and R' represents a C alkyl or aryl group or together represent a Ceycloalkyl group;

n and m represent an integer or from 2 to 6; and

p and q represent 0 or an integer of from 1 to 50, and

at least p or q 0.

2. A fiber, thread, or foil as described in claim 1 wherein thepolyacrylonitrile polymer contains the compound \c N cH -cH -o) c NH(CH2)|7-CH3 3. A fiber, thread or foil as described in claim 1 whereinthe polyacrylonitrile polymer contains the \/N (CH2CH2O)7 5-H II o 4. Afiber, thread or foil as described in claim I vwherein thepolyacrylonitrile polymer contains the compound 3 CH -N II o 5. A fiber,thread or foil as described in claim 1 wherein the polyacrylonitrilepolymer contains the CH (CH 6. A fiber, thread or foil as described inclaim 1 wherein the polyacrylonitrile contains the compound 3,928,298 L-.11 l2 C ontinued. r where n is 8 or 19 8; A fiber,'thread, or foil asdescribed in claim 1 wherein the polyacrylonitrilecontains the compound7. A fiber, thead, or foil as described in claim 1 n wherein thepolyacrylonitrile contains the compound v 0 CH v CH O O CH CH CH (CHHN-C (O-CH -CH -N N- 3 2 2 2 n -N N- cu -cn -o II o 2s o (cu cn -m-c-nn-jcl-t cn I i Patent No. 3 928 Dated December 23, 1975 GerhardDieter Wolf et a1. Inventor(s) It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 1, line 46, "on" should read or Signed and Scaled thisThirty-first Day of May 1977 [SEAL] RUTH C. MASON C. MARSHALL DANN ffCommissioner nj'lare'nls and Trademarks

1. A FIBER, THREAD OR FOIL OF A SYNTHETIC POLYACRYLONITRILE POLYMER WITHPERMANENT ANTISTATIC PROPERTIES, WHICH CONTAINS 0.5-15 PERCENT BY WEIGHTOF THE TOTAL, OF POLYETHERS CONTAINING HYDANTOIN RINGS AS REPRESENTED BYTHE FORMULA
 2. A fiber, thread, or foil as described in claim 1 whereinthe polyacrylonitrile polymer contains the compound
 3. A fiber, threador foil as described in claim 1 wherein the polyacrylonitrile polymercontains the compound
 4. A fiber, thread or foil as described in claim 1wherein the polyacrylonitrile polymer contains the compound
 5. A fiber,thread or foil as described in claim 1 wherein the polyacrylonitrilepolymer contains the compound
 6. A fiber, thread or foil as described inclaim 1 wherein the polyacrylonitrile contains the compound
 7. A fiber,thead, or foil as described in claim 1 wherein the polyacrylonitrilecontains the compound
 8. A fiber, thread, or foil as described in claim1 wherein the polyacrylonitrile contains the compound